12 – The jurists have set ten conditions for the validity of qasāmah:

First: the presence of al-luth. According to the authoritative position in the school this means manifest enmity, like that which once existed between the Helpers and the people of Khaybar. A second report defines al-luth as the soundness of the qasāmah claim together with a strong presumption of the defendant’s guilt based on compelling circumstantial clues. This second view was preferred by Ibn al-Jawzi and Shaykh al-Islam Ibn Taymiyyah; al-Mardāwī states in al-Insāf that it is the correct position and the view of al-Shāfiʿī.

Second: the accused must be legally accountable (mukallaf), for no claim can be directed against one who is not accountable.

Third: it must be physically possible for the accused to have carried out the killing; if that is impossible—for example because he is chronically disabled—the claim is void, just as any allegation that the senses declare impossible.

Fourth: the manner of the killing must be specified in the claim, such as saying, “He struck him with his sword at such-and-such place on his body.”

Fifth: all the heirs must jointly pursue the claim of murder; mere absence of contradiction among them is not enough, for silence carries no legal effect.

Sixth: all heirs must request that qasāmah be invoked; a request by only some of them is insufficient, since no single heir holds the right exclusively.

Seventh: the heirs must unanimously affirm that the death was the result of homicide; if any heir denies that it was murder, qasāmah is not instituted.

Eighth: the heirs must also agree on the identity of the killer; if some say, “Zayd killed him,” while others say, “It was Bakr,” qasāmah cannot proceed.

Ninth: among the heirs there must be male, legally accountable persons, for qasāmah is employed to establish intentional homicide. Consequently, the oaths of women are not accepted, nor is an heir who lacks legal competence or who declines to swear allowed to participate.